The present invention relates to reservoir caps, and, more particularly, to a cap for a fluid reservoir of a master cylinder associated with a brake circuit in a vehicle.
During the manufacture of a motor vehicle, the brake circuit is installed, exhausted and then filled with hydraulic fluid. As a general rule, these operations are handled through the master cylinder fluid reservoir and make it necessary for the reservoir cap first to be removed, the cap then being replaced on completion of the filling. This series of operations does not lend itself to the assembly line production of a motor vehicle, in which the operations are increasingly frequently carried out by machine. Moreover, motor vehicle manufactures wish to be able to effect the filling of the brake circuit in a simple, automated manner.
It is known from WO-A-84/01546 a connection system between a reservoir located on a vehicle and a container filled with the fluid, both recipients having complementary ends allowing a fluid-tight relationship with a foolproofing item avoiding the filling of the reservoir with a container different that the right one.
According to this document, the reservoir may include a spout extending outwardly, provided for entering an opening of the container and for depressing a cover, which allows the transference of the fluid from one to the other.
This invention is not concerned by a foolproofing item for avoiding undesirable mixture of liquids as the above mentioned document does, but it provides a cap for a reservoir of brake liquid, allowing a speedy filling without disassemblying, and comprising a vent passage, and valve means in the cap axis.